The Mountain Air Force Station in Los Angeles, California

Mountain Air Force Station produced motion pictures and still photographs for the United States Department of Defense. The 100,000 square feet facility was built on two and a half acres in 1941 as a World War II air defense center to coordinate Los Angeles area radar installations. When the studio was established in 1947, its purpose was kept secret. It was declared Los Angeles historic cultural monument number 1098 in 2015.